Re: Deferring some AtStart* allocations?

On 2014-10-08 13:52:14 -0400, Robert Haas wrote:
> On Sun, Jun 29, 2014 at 9:12 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Meh. Even "SELECT 1" is going to be doing *far* more pallocs than that to
> > get through raw parsing, parse analysis, planning, and execution startup.
> > If you can find a few hundred pallocs we can avoid in trivial queries,
> > it would get interesting; but I'll be astonished if saving 4 is measurable.
>
> I got nerd-sniped by this problem today, probably after staring at the
> profiling data very similar to what led Andres to ask the question in
> the first place.

I've loolked through this patch and I'm happy with it. One could argue
that the current afterTriggers == NULL checks should be replaced with a
Assert ensuring we're inside the xact. But I think you're right in
removing them, and I don't think we actually need the asserts.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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